Credit guarantee organizations（CGOs）are introduced to financing process of small and medium-sized enterprises（SMEs）.It can decrease financing drawbacks such as insufficient mortgages and credit registers of SMEs，enhance their credit ranks and share in loan risks of finance institutions.So foreign economists thinks that credit guarantee is one of effective instruments by which many governments support SMEs' development，either in theory or in operation.Since 1920s，policy，mutual and commercial CGOs are successively found.They have exerted significant role in resolving the difficulties of SMEs financing，upgrading credit level of SMEs and developing and consummating Chinese credit system.

Whereas Chinese credit guarantee system faces a material question that must be settled in time，and it has been attented by some governments，experts and scholars.China need select a credit guarantee dominant mode among three kinds of CGOs.Afterwards whether other modes should be developed or not and how other modes should be developed.Furthermore，three kinds of CGOs are confronted with some external and internal problems.If they are not solved in season，rapid development and perfecting of CGOs and credit guarantee system will be blocked.Thereby they are essential that current situation and characteristics of three kinds of CGOs are deeply and systemicly studied，and that credit guarantee main mode is set up，and that some countermeasures and steps are put forward.These researches have theoretical and practical sense in dredging financing channels of SMEs，promoting the development of SMEs，pointing out evolution direction of CGOs and enriching the theory and practice of Chinese credit guarantee.

Guided by science of public management，western economics，information economics and other theories，this book studies establishing the credit guarantee dominant mode and giving appropriate countermeasures and suggestions to three sorts of CGOs.In the paper，some research methods are used，such as theoretical and empirical analysis method，qualitative and quantitative analysis method.The main content is as follows：

（1）Introduction.This chapter expatiates the backgroud and theoretical and practical meaning of the subject，concludes and values domestic and foreign research literatures about credit guarantee，designs technique route and this thesis's framework and brings forward correlative research ways.

（2）Study on credit guarantee for SMEs and correlative theories.At first，the chapter defines credit guarantee and its basic category，and sets forth the connotation and sorts of credit guarantee mode for SMEs；whereafter introduces existing rationality theory CGOs for SMEs on condition that information is asymmetry；at last，two sorts of game model with complete and incomplete information are separately established to three kinds of CGOs according to game theory.

（3）The operation of foreign CGOs for SMEs and apocalypses.This chapter mainly concludes operation situation and characteristics of foreign CGOs，such as policy credit guarantee of Japan，America and other countries，mutual credit guarantee of Italy and other countries，and commercial credit guarantee of America and other countries.By comparation and analysis，experiences and moduses of foreign CGOs are summarized and good revelations are concluded.The revelations are available to establish appropriate guarantee model and development experiences.

（4）Analysis on current situation of Chinese CGOs for SMEs.Firstly，the chapter recommends evolution，current situation，general peculiarities of Chinese credit guarantee；and then analysizes external environment of three kinds of CGOs；finally，current situation and problems of different CGOs are described.

（5）Comparative analysis on three kinds of CGOs in China.Guided by theory of vicinal public goods guarantee，enterprise finance and others，this chapter analysizes the important role and status of policy CGOs among Chinese guarantee system.Secondly financing contribution and efficiency of three kinds of CGOs are compared by hypothesis and establishing model.Thirdly it is analyzied that commercial CGOs promote financing of SMEs；At last，service range，fund source，function of three kinds of CGOs are compared.

（6）Empirical study on credit guarantee model for SMEs.At first，this chapter introduces the investigation background and implement situation.Secondly，general situation of Jiangsu CGOs and basic situations of three kinds of CGOs are analysized by descriptive statistics method，and economic and social benefits of three kinds of CGOs are compared.Finally，20 samples among investigated CGOs are choosed and principal component analysis are made.

（7）Selecting dominant model of credit guarantee for SMEs and countermeasures.Based on theoretical analysis andempirical study on Chinese three kinds of CGOs，this chapter advances the dominant model and framework of Chinese credit guarantee for SMEs，that is，persisting in the leading status of policy CGOs duratively，elaborating sufficiently the complementary role of mutual CGOs，and promoting the normative progress of commercial CGOs.On the basis of above content，good countermeasures and suggestions are put forward to optimizing exterior environment promoting the development of three kinds of CGOs.

（8）Conclusion and prospect.The chapter summarizes the full book，educes some conclusions，and indicates the limitations of the thesis and some subjects which should be further studied in this area.

Through research，the book has some conclusions：

（1）According to information economics the article advances basic route that resolve informationasymmetry during guarantee process for SMEs.It is realized by mathematical analysis on credit guarantee for SMEs on condition of information asymmetry.

（2）By establishing game model and making information analysis on three kinds of CGOs，it is showed that knowing risk distributing of enterprises and corresponding benefits is critical to guarantor andlender，repayment willness and guarantee style is especially important to enterprises.

（3）On the basis of the experences from America，Japan，Italy and other countries，This paper demonstrates that policy CGOs should be the main body of Chinese credit guarantee system.

（4）External environment factors that areadverse to the development of three kinds of CGOs are：lagged guarantee laws and systems building，inadequate effectivity of credit guarantee supervision and administration system，not good social credit environment，low acceptence of finance institutions to CGOs，and incomplete credit reguarantee system.

（5）Through theoretical analysis，this article thinks that our government should insist on the dominant status ofpolicy CGOs，and that mutual CGOs and commercial CGOs should be positively supported.

（6）Byempirical analysis on 20 CGOs in Jiangsu Province，economic and social returns of policy CGOs are comparatively notable.

（7）The main conclusion of the thesis is persisting duratively in the dominant status ofpolicy CGOs，exerting sufficiently the complementary role of mutual CGOs，and promoting commercial CGOs to develop canonically.

（8）Consummating the exterior circumstance of credit guarantee needs some measures：establishing andstrengthening guarantee laws and systems，boosting up the validity of guarantee supervision and administration system，perfecting social credit circumstance and other steps.Finally the thesis provides different countermeasures and suggestions for three kinds of CGOs.